In 1609 Galileo heard that a new instrument had been invented in the Netherlands which made objects in the distance seem close to the observer. Galileo tried to create this using a variety of lenses and he soon succeeded in making a basic telescope using a concave and a convex lens at either end of a lead tube. At the third attempt he produced a telescope that made objects appear 1 000 times larger and over thirty times closer than seen with the naked eye. Although Galileo could see the importance of the telescope's aid to navigation at sea and over land, he was most interested in its use to look at the skies.
Through the telescope, Galileo observed that the surface of the moon appeared pitted with craters. There were mountain peaks lit by the sun's light and other parts that remained in darkness. Galileo then turned his telescope to view the stars, but found that unlike the moon, the stars were hardly magnified. He was, however, overwhelmed by the hundreds of stars that suddenly became visible. The Milky Way, which to the naked eye had been just a pale uncertain glow, viewed through a telescope was revealed as a myriad of individual stars.
On 7 January 1610, Galileo observed three very bright objects close to Jupiter. After observing these over a number of nights, he noticed that the pattern changed and a fourth bright object became visible. Galileo explained there were four satellites which revolved about Jupiter and Jupiter and its satellites revolved around the sun.
Through the telescope, Galileo observed that the surface of the moon appeared pitted with craters. There were mountain peaks lit by the sun's light and other parts that remained in darkness. Galileo then turned his telescope to view the stars, but found that unlike the moon, the stars were hardly magnified. He was, however, overwhelmed by the hundreds of stars that suddenly became visible. The Milky Way, which to the naked eye had been just a pale uncertain glow, viewed through a telescope was revealed as a myriad of individual stars.
On 7 January 1610, Galileo observed three very bright objects close to Jupiter. After observing these over a number of nights, he noticed that the pattern changed and a fourth bright object became visible. Galileo explained there were four satellites which revolved about Jupiter and Jupiter and its satellites revolved around the sun.